This question has been asked and answered by those in the know on this site many times. I had the same concern and still do to this day after 8,600 miles. I even get it some times between 5th and 6th gear. They say its normal. I still don't think clunks are normal. Even two dealers told me its normal. Thats why we have a 5yr 100,000 drive train warranty I guess. Not to worry.

Yeah if you never mod it. This is supposed to be american muscle. Retune your computer and see how well they support that warranty.